Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description goes further by disclosing the auth prerequisite (API key with pwk_live_ prefix from a specific profile URL) and the failure contract (error.code, error.message, error.http_status, error.retry_recommended, error.retry_after_seconds), which is genuinely beyond the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences, front-loaded with the core action before the auth and error details. No filler, though the error-field enumeration is slightly list-heavy for a read tool whose output schema already exists.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a two-parameter read tool with an output schema and full annotation coverage, this covers credentials, the identifier source, and failure behavior. Only the when-to-choose-this-over-siblings decision is left unstated.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description still adds value by restating the key format and linking the URL where the key is issued, plus the error fields that parameters feed into.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Get one price alert by alert_id'), which separates it from the list/get-history siblings by scope. It never names an alternative tool, so sibling differentiation is implied rather than explicit.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies single-record lookup, but offers no when-to-use guidance or exclusions relative to list_price_alerts or get_price_history. The only routing aid is the alert_id provenance note that lives in the schema, not the description.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.